Proceedings Paper

The recent advent of laser guide star adaptive optics (LGS AO) on
the largest ground-based telescopes has enabled a wide range of high
angular resolution science, previously infeasible from ground-
and/or space-based observatories. As a result, scientific
productivity with LGS has seen enormous growth in the last few
years, with a factor of ~10 leap in publication rate compared to the
first decade of operation. Of the 54 refereed science papers to
date from LGS AO, half have been published in the last ~2 years, and
these LGS results have already made a significant impact in a number
of areas. At the same time, science with LGS AO can be considered
in its infancy, as astronomers and instrumentalists are only
begining to understand its efficacy for measurements such as
photometry, astrometry, companion detection, and quantitative
morphology. We examine the science impact of LGS AO in the last few
years of operations, largely due to the new system on the Keck II
10-meter telescope. We review currently achieved data quality,
including results from our own ongoing brown dwarf survey with Keck
LGS. We assess current and near-future performance with a critical
eye to LGS AO's capabilities and deficiencies. From both
qualitative and quantitative considerations, it is clear that the era
of regular and important science from LGS AO has arrived.